[services] Tests - Run formatter

Summary:
Depends on D4555

Running rust formater on the tests.

Test Plan: None really, it's just code styling, the code compiles and runs as before.

Reviewers: tomek, varun

Reviewed By: tomek, varun

Subscribers: ashoat, tomek, adrian, atul, abosh

Differential Revision: https://phab.comm.dev/D4598